Cam means



Nov. 15, 1966 D. c. ROCKOLA CAM MEANS Filed Dec. 11, 1964 INVENTOR DAVIDC ROCKOLA 09%,6/2M5/WM ill/L275.

United States Patent 3,285,095 CAM MEANS David C. Rockola, Chicago,Ill., assignor to Rock-Ola Manufacturing Corporation, Chicago, 111., acorporation of Delaware Filed Dec. 11, 1964, Ser. No. 417,727 Claims.(Cl. 74-568) This invention relates generally to mechanical motiontransmitting means and more specifically to improvements in plate cammeans,

The utilization of rotatably driven plate cam means for actuating rollerfollowers is well known in the art. Generally, such plate cam means havea fixed profile or periphery along which is suitable follower, usually aroller, moves to actuate an attendant linkage or arm in a predeterminedmotion pattern. For a number of years the use of simple plate cams astime actuator means for switches, wherein the switch contacts are madeand brok en in response to actuation of a cam following actuator arm hasgained widespread acceptance. Usually in such an arrangement the camplate is rotatably driven by a shaft at constant rpm. and the camprofile is such as to include a pair of riser nodes, spaced at suitablearcuate distance determinative of a fixed time interval according to therotational speed of the driven cam plate. The remainder of the camprofile provides an additional time interval; each of which intervalsmay be employed, as selected, for switch open or switch closed periods.Thus a convenient and simple yet operationally reliable switch timingmechanism is evolved according to practices familiar to those skilled inthe art. Such time switch operation by the use of *rotatably driven camplates is adapted to a wide variety of operations, but generally isrestricted to conditions wherein fixed on and off times are encountered.It will be readily recognized that in this context the on and offperiods for the switch arrangement associated with the cam follower arenecessarily of a predetermined extent as established by the fixed andinflexible profile of the familiar actuating cam plates. For some timethis simplified system has suffered limitation of use because of theinherent inflexible characteristics of the fixed cam profile or statedotherwise, such system defies adjustment of the switch on and off timesfor a given cam. To date the usual solution to this limitation is toreplace the cam with another having a different profile. It is to a newand improved solution of this particular problem in the art that thepresent invention is directed.

In brief, the present invention contemplates a unitary plate 0am means,adapted to be driven with and by a rotatable shaft means and which issusceptible of adjustable variation of its profile in an easy andconvenient manner so as to regulate the relative positioning of risernodes thereof to correspondingly permit alteration of the responsiveactuation of a follower engaging the cam profile. In general theimproved cam means of this invention includes two or more plate cams,each with a fixed profile, mountable on a common hub for rotationtherewith. At least one of the said cams is affixed to the hub and atleast one other is rotatable about the hub and relative to the one camaffixed thereto. With this arrangement the relative positioning ofadjacent cam plates commonly engagable by a single roller follower orthe like, readily permits the user to regulate the arcuate spacingbetween riser nodes so as to correspondingly alter the operationallyeffective extent of the major and minor profile portions of the cammeans and consequently regulate the time intervals during which thefollower engages the red ice ially inward and outward profile portionsof the cam :means. Thus operating time intervals for a switch or othermeans, associated with the follower, are adjustable according to theparticular operational demands of an encountered operating sequence orcircumstance. Additional means are provided in the improved cam means ofthis invention for frictionally interlocking the several cam plates ofthe combination so as to maintain their selected inter-positioningproductive of a selected cam profile; said profile though adjustablebeing nevertheless operationally stable for a given selected positioningof parts,

The main object of this invention is to provide a new and improved cammeans having an adjustable profile.

Another object of this invention is to provide a new and improved cammeans comprising a plurality of adjacent cam plates, each with a fixedprofile cooperatively associated in such a manner as to produce acomposite cam means of adjustable profile.

Another object of this invention is to provide new and improved cammeans which is particularly adapted for timing mechanism whereby therotational driving of the cam means at a constant r.p.m. accompanied byselected adjustment of its profile permits the user to selectively alterthe operating-position periods of a follower engaging the periphery ofthe cam means.

A still further object of this invention is to provide new and improvedcam means readily usable in timing mechanism which embodies simplifiedmeans for adjusting the profile thereof while being operationallydependable.

A still additional object of this invention is to provide new andimproved cam means as aforesaid which is inexpensive to manufacture andassemble and which provides the user with improved and simplifiedadjustibility of the actuating peripheral profile presented thereby.

Having thus described the present invention the best mode presentlycontemplated for carrying out its concepts and features will now bedescribed in association with a preferred embodiment thereof,illustrated in the accompanying drawings, which taken with thehereinafter set forth description will serve to amplify and further setforth the above and further objects, features and advantages of thisinvention.

In the drawings:

FIG. 1 is :a rear elevational view of the improved cam means of thisinvention;

FIG. 2 is a front elevational view thereof;

FIG. 3 is an end elevational view thereof; and

FIG. 4 is a cross-sectional view taken substantially at line 44 of FIG.2 and looking in the direction of the arrows thereon.

Referring now to the drawings, it will be understood from FIGS. 1 and 2,in particular, that the improved cam means of this invention, indicatedgenerally at numeral 10 therein, comprises a plurality of cam plates,namely plates 11 and 12 in the illustrated embodiment, mounted on acommon hub means 13 for rotation with the latter and a driving shaft 14connectively associated with the hub means 13 (see FIGS. 3 and 4). Thecombination of this invention further includes suitable locking means 15for fixedly coupling one of the cam plates, such as plate 11, to the hub13' and clutch means 16 for releasably coupling the other cam plate 12to the hub 13 and adjacent cam plate 11. Means 17 are also provided onor in association with the movable cam plate 12 for receiving suitablewrench or other engaging means (not shown) whereby the movable cam plate12, may be rotatably moved about hub 13 and relative to the cam plate 11affixed to said hub. Adjustable variation of the peripheral profile, forcam means 10 is visually indicated by index means comprising scale means18 and 19, on the cam plates 11 and 12, respectively.

Turning now in greater detail to the particulars of the severalelementary means comprised in the improved combination of thisinvention, as shown best in FIGS. 1 and 2, cam plate 11 is constructedwith a substantially planar body portion 20, preferably of metal orother rigid material, such as steel and the like, which is suitablycontoured to present a major semi-circular peripheral profile portion 21and a minor semi-circular peripheral profile portion 22 interjoined attheir contiguous ends by intervening riser profile portions 2323. Inthis regard it will be understood and appreciated that the profileportions 21 and 22 need not be semi-circular since the particularprofile for the cam plate 11 as well as the form and number of riserportions 23--23 thereof may be widely varied and selected according torecognized skills and knowledge of the art according to the presentinvention. Essentially the profile of cam plate 11 presents a continuousperipheral edge engageable by a roller or a similar follower means 24adapted to ride along radially inner and outer paths, as it engages thecarns minor and major profile portions 22 and 21 respectively. As theroller engages either of the riser portions 2323 the same transfers toand between the major and minor profiles of the cam plate according torecognized principles.

Cam plate 11 is particularly distinguished by an enlarged centralcircular opening 25 adapted to fit concentrically about the hub member13 as will be amplified in greater detail presently. The circularperiphery of opening 25 is periodically interrupted by several (four asillustrated) spaced semi circular staking openings 26-26 which cooperatewith the locking means 15 for rigidly afiixing and associating thecamplate 11 on and with the hub member 13, in a manner to be described morefully hereinafter. For convenience sake the one scale means 18 isassociated with the cam plate 11; the same being inscribed or otherwisepresented on one front face 28 of such plate contiguous to the majorprofile portion 21 thereof (see FIG. 2).

In the particular embodiment of the improved cam means of this inventionillustrated in the drawings, cam plate 12, as shown best in FIG. 2, isformed substantially of identical shape, size and contour and peripheralprofile as the above described cam plate 11. Thus, cam plate 12comprises a substantially planar body portion 30 having a majorsemi-circular profile portion 31 and a minor semi-circular profileportion 32 which correspond to portions 21 and 22 respectively of theabove described cam plate 11. The major and minor profile portions ofcam plate 12 are likewise interconnected at their contiguous ends byintervening riser portions 33-33 whereby the roller means 24 engagingthe periphery of cam plate 12 is enabled to translate between the majorand minor profile portions thereof according to familiar practice. Likecam plate 11, cam plate 12 is provided with an enlarged central opening35 which is adapted to fit concentrically about the central hub member13.

Unlike cam plate 11, cam plate 12 is equipped with a plurality ofopenings 37 located radially inwardly of its periphery and which arespaced at suitable arcuate intervals, approximately 45 intervals, asillustrated, to provide a plurality of wrench or other tool engagingmeans 17, hereinabove referred to, whereby the cam plate 12 may beengaged and rotated about the hub 13 and relative to cam plate 11 aswill appear presently. For convenience the secondary scale means 19 isdisposed, as by inscribing, on the front face 38 of the cam plate 12adjacent the minor peripheral portion 32 thereof so as to becooperatively associated visually with the scale means 18 appearing onface 28 of the cam plate 11 all as best shown in FIG. 2 of the drawings.

The hub member 13 as herein illustrated comprises a substantiallycylindrical metal member having a central axial opening 40 machinedtherethrough for receiving the drive shaft 14. In order to provide aconvenient means for preventing rotational movement of the hub member 13relative to and about shaft 14, one side of opening 40 is formed wiht aplanar chord-a1 portion 41 which is adapted to matingly engage aflattened or cut-away area of the shaft 14 to provide an interlockingsystem for keeping the hub member from rotating relative to the shaftmember.

As seen best from FIG. 4 of the drawings, the hub member 13 comprises anenlarged cylindrical collar portion 42 formed at one axial end 43thereof and a cylindrical shoulder portion 44 extending coaxiallyoutwardly of the collar portion 42; said shoulder portion 44 being oflesser diameter thanthe collar portion 42 with the circumferentialsurfaces of the portions 43 and 44 being concentric and interjoined byan intervening annular shoulder surface 45. The diameter of thecylindrical shoulder portion 44 is just slightly smaller than thecentral opening 35 of the cam plate 12 whereby the latter may beconcentrically disposed about and supported on the shoulder portion 44.

Adjacent its outermost end the shoulder portion 44 is formed with adiametrically reduced cylindrical end portion 46 which is receivedclosely within the central opening 25 of the cam plate 11 when thelatter is as sembled on the hub member. In this respect it will berecognized that an annular staking shoulder 47 is formed between theconcentric cylindrical surfaces of the shoulder and end portions 44 and46 for purposes to be amplified presently.

In assembling the two cam plates 11 and 12 with and on the hub member13, the one cam plate 12 having the wrench engaging means 17 associatedtherewith is disposed on and about the shoulder portion 44 nearest 'theshoulder surface 45 of the hub member, but separated therefrom by aninterposed frusto-conical unitary annular spring member, comprising thepreviously mentioned clutch means 16 as best illustrated in FIGS. 3 and4 of the drawings. Fixing of cam plate 11 to the hub member 13 so as toprevent relative rotation therebetween, is accomplished by means of thelocking means 15 constituting upset stake portions 50 formed on theperiphery of the hubs end portion 46 by axially punching such peripheryopposite each staking opening 26 of the cam plate 11 according to knownstaking practice. By this convenient and simple expedient the materialupset from the end portion 46 of the hub is coldflowed into the stakeopenings 26 pressing the cam plate 11 tightly against the stakingshoulder 46 and fixing the same with and on the hub member 13. In suchassembly of cam plates 11 and 12 on the hub means 13 there is a slightaxial compression of the frusto-conical spring clutch means 16 betweenface 38 of cam plate 12 and the shoulder face 45 of the hub means 13.

By the combination of parts as above described, it will be appreciatedand understood that the cam plate 11 is fixed to the hub means 13 whilecam plate 12 is rotatable relative thereto and cam plate 11. Further,while the cam plate 12 is so relatively rotatable its rotationalmovement is not free and unhampered, but is frictionally regulatedaccording to the coupling activity provided by the compressed clutchmeans and the interengaging or opposing faces of the two cam plates 11and 12. In a similar fashion the engagement of the surface 38 on camplate 12 and the larger diametered or base edge of the frusto-conicalclutch means 16 provides additional frictional interference withrotation of the cam plate 12.

While the cam plate 12 is frictionally interlocked with both the camplate 11 and a hub member 13 as above described, such frictionalinterlocking is of a nature to permit regulated rotation or movement ofthe cam plate 12 relative to the cam plate 11 and hub means 13,particularly upon the application of suitable torque to the cam plate 12while maintaining the hub member 13 and the attached cam plate 11stationary with shaft 14. The application of such force to rotate camplate 12, as selected, is conveniently applied by virtue of the Wrenchengaging openings 37 in cam plate 12 which permit the user to apply atorque wrench or other leverage means thereto, in a known manner. Thusit will be readily recognized and appreciated that plate 12 may beselectively moved relative to cam plate 11 so that the compositeperipheral contour or profile of the cam means of this invention maybeaccordingly adjusted and changed as selected.

Amplifying the foregoing, it will be understood that if the cam plate 12is rotated: from its FIG. 2 position for example, while maintaining camplate 11 relatively stationary with respect thereto, the major and.minor peripheral portions of the two cam plates selectively may bepositioned at or between one limit position wherein their like profilescoincide and a second position wherein the major profile portion of onecam plate lies substantially coextensively opposite the minor profileportion of the other cam plate. This particular relationship and rangeof adjustability occurs in the presently illustrated example of theinvention by virtue of the fact that the cam plates 11 and 12 are oflike size and peripheral shape with the major and minor peripheralportions of each constituting substantially 180 of their respectivecircumferences. As previously mentioned cam plates 11 and 12 may be ofeither like or unlike formation so that the peripheral extent of themajor and minor profile portions of each may be widely varied toaccordingly provide a wide variety of peripheral shapes for cam means 10differing materially from those attainable by the particular cam plates11 and 12 shown. It also must be recognized that more than two camplates may be utilized to provide an even greater range of adjustablechange for the periphery of the cam means 10 of this invention.

In order to assist the operator in adjustably positioning cam plate 12with respect to plate 11, the two cooperating scale means 18 and 19 areprovided, the graduations of the scale means 18 constitute 5 arcuate1nterval while the graduations of scale means 19 are substantially 30apart in the particular embodiment illustrated. Such scale means, ofcourse, may be varied, as selected, according to the particularrequirements and demands of a given installation without departing fromthe present invention.

From the foregoing it is believed that those skllled in the art willreadily recognize and appreciate the novel merits of the presentinvention which serve to mark the same apart from prior known cam means.Additionally apparent from the foregoing description of the presentinvention is the fact that the regulated interpositionlng of the two camelements serves to eifectively change the peripheral contour of the cammeans which accordingly regulates the inward and outward movement of thefollower means, such as a roller follower 24 engageable with suchperiphery. Thus a convenient composlte cam means, having a readilyadjustable and flexible contour capable of affording the user a new andsimple operationally stable and dependable means having particularuntility in adjusting the timing cycles of attendant mechanisms isprovided by this invention; the timing being altered principally byutilization of a constant selected r.p.m. for the cam means so thatchange of the arcuate interspacing between successive riser portions 23and 33 presented to the follower means will accordingly vary the timeperiods in which the follower means engages the effective major andminor profile portions of the composite cam means.

Having thus described the present invention it is belived that thosefamiliar with the art will readily recognize and appreciate the featuresand advantages of the present invention whereby its objectives arecarried out. Further while the present invention is hereinabovedescribed in association with a particular preferred and simplifiedembodiment thereof illustrated of the accompanying drawing, it willnevertheless be understood that such embodiment may be subject tomodification, change and substitutions of equivalents without departingfrom the spirit and scope of this invention. Consequently it is intendedthat this invention be unlimited by the foregoing description except asmay appear in the following appended claims.

I claim:

1. In combination, a hub member adapted to be rotatably driven, pluralcam plates adjacently mounted on said hub member for coaxial rotationtherewith, each of said plates having fixed peripheral cam profileportions, means affixing one of said cam plate to said hub member, meansrotatably mounting another of said cam plates on said hub member wherebythe same may be rotatably moved thereabout and relative to said one camplate, unitary clutch means operative to normally interlock said camplate and selectively release said another cam plate upon rotation ofthe latter about said hub member whereby the said fixed peripheral camprofile portions of said cam plates may be selectively related andarranged to provide a plurality of selected composite profiles for saidcam means, and means for coupling torque applying means to said othercam plate to effect said rotation thereof.

2. Plate cam means comprising a hub member adapted to be rotatablydriven and having coaxial cylindrical shoulder and collar portions, apair of cam plates each having a fixed peripheral profile with major andminor portions interjoined by riser portions, means fixedly connectingone of said plates to said hub member adjacent one end of said shoulderportion thereof, means rotatably mounting the other said plate onsaidshoulder portion contactingly adjacent said one plate and axially spacedfrom said collar portion unitary clutch means mounted on said shoulderportion in frictional engagement with said collar portion and said otherplate, said clutch means serving to frictionally interlock said otherplate with said hub member whereby the said plates are normallyconjointly rotatable with said hub member, and wrench engaging means onsaid other plate for the attachment of torque applying tool meansthereto whereby said other plate may be rotated relative to said oneplate and said hub member in defiance of said frictional interlock, therotation of said other plate relative to the said one plate serving toalter the relative positions of their respective profile portions tothereby present various selected composite profiles for said cam meanseffective to actuate follower means engaging the same.

3. The combination set forth in claim 2 wherein said clutch meanscomprises unitary annular spring means.

4. Improved cam means comprising a hub member adapted to be rotatablydriven, a pair of cam plates adjacently mounted on said hub member forconjoint rotation therewith, each of said cam plates having a fixedperipheral profile, means fixedly attaching one of said cam plates tosaid hub member, means mounting the other of said cam plates on said hubmember for rotation thereabout and relative to said one cam plate asselected, clutch means comprising spring means frictionally engagingsaid hub member and said other cam plate and serving to releasablyinterlock said cam plates whereby said other cam plate may be moved toand locked in selected positions relative to said one cam plate, andmeans for effectively releasing said clutch means to permit saidmovement of said other cam plate.

5. Improved cam means comprising a hub member adapted to be rotatablydriven, a pair of cam plates adjacently mounted on said hub member forconjoint rotation therewith, each of said cam plates having a fixed a 7V I 8 peripheral profile, means fixedly attaching one of said ReferencesCited by the Examiner cam plates to said hub member, means mounting theUNITED STATES PATENTS other of said cam plates on said hub member forrotation thereabout and relative to said one cam plate as 2,096,18210/1937 Kerr et 74 '568 selected, clutch means releasably interlockingsaid cam 5 FOREIGN PATENTS g? ZZffi 3 .fF i i t0 936,660 2/1948 France.an 0: in se ec e P081 1011 re a we 0 sm one cam 1,199,109 6/1959 Planetplate, and means for effectively releasing said clutch means to permitsaid movement of said other cam plate comprising means on said other camplate for applying torque 10 thereto sufiicient to rotate the same aboutsaid hub mem- FRED MATTERN Primary Exammer' her in defiance of saidclutch means. W. S. RATLIFF, Assistant Examiner.

182,484 4/ 1907 Germany.

1. IN COMBINATION, A HUB MEMBER ADAPTED TO BE ROTATABLY DRIVEN, PLURALCAM PLATES ADJACENTLY MOUNTED ON SAID HUB MEMBER FOR COAXIAL ROTATIONTHEREWITH, EACH OF SAID PLATES HAVING FIXED PERIPHERAL CAM PROFILEPORTIONS, MEANS AFFIXING ONE OF SAID CAM PLATE TO SAID HUB MEMBER, MEANSROTATABLY MOUNTING ANOTHER OF SAID CAM PLATES ON SAID HUB MEMBER WHEREBYTHE SAME MAY BE ROTATABLY MOVED THEREABOUT AND RELATIVE TO SAID ONE CAMPLATE, UNITARY CLUTCH MEANS OPERATIVE TO NORMALLY INTERLOCK SAID CAMPLATE AND SELECTIVELY RELEASE SAID ANOTHER CAM PLATE UPON ROTATION OFTHE LATTER ABOUT SAID HUB MEMBER